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HP Forum Archive 20

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HP-15C LE Bad Button >>> easy fix
Message #1 Posted by Reth on 24 Nov 2011, 5:30 p.m.

In a previous thread we saw HP-15C LE fixed, but I found that fix too complicated. So I decided to sacrifice my calculator and do it myself and I'm no good with such repairs.

I used only my Swiss army knife, a small screwdriver and two component epoxy glue.

Heat stakes are very easy to cut off flashing with the PCB - the plastic the are made of is somewhat soft, jelly like.

The offending key had a little white plastic ball - about 0.1mm diameter - stuck at the dead center of the metal dome - and I had to apply some force to remove it.

I can't tell more about the material of the "ball", it got lost somewhere in the cotton bud I used to take it off...

Reassembling was easy - PCB stood quite firmly even without heat stakes heads being glued - I tested it like that for a day. Eventually I put a little drop of the glue on top of the heat stakes and that way sealed them. I believe this is enough to keep it firmly in place.

A tricky bit is there are 3 little spiral springs abt 20mm long that are very easy to loose when opening the calculator.

It's working perfectly now - will see for how long ;)


Edited: 24 Nov 2011, 8:14 p.m. after one or more responses were posted

Re: HP-15C LE Bad Button -> easy fix
Message #2 Posted by Raymond Del Tondo on 24 Nov 2011, 6:21 p.m.,
in response to message #1 by Reth

Many thank for the info:-)

did you take pictures of the work?

Could the plastic ball be a residue from manufacturing, or in other words: Is it of one of the materials used in the hardware?

Did you mail it (the info, not the piece) to Tim? This may be of interest for him;-)



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